Determines where in the filter chain this `WasmPlugin` is to be injected.

                  Valid Options: AUTHN, AUTHZ, STATS
                enum:
                - UNSPECIFIED_PHASE
                - AUTHN
                - AUTHZ
                - STATS
                type: string
              pluginConfig:
                description: The configuration that will be passed on to the plugin.

  E0303 17:25:03.436781 63839 summary_sys_containers.go:47] Failed to get system container stats for "/docker": failed to get cgroup stats for "/docker": failed to get container info for "/docker": unknown container "/docker"

## API Changes

*   Rename `SqueezeDims` attribute to `Axis` in C++ API for Squeeze op.
*   `Stream::BlockHostUntilDone` now returns Status rather than bool.
*   Minor refactor: move stats files from `stochastic` to `common` and remove
    `stochastic`.

## Known Bugs

*   Using XLA:GPU with CUDA 9 and CUDA 9.1 results in garbage results and/or
    `CUDA_ILLEGAL_ADDRESS` failures.